1. Field of the Invention
The invention relates to lined tubular assembly and to a method and apparatus for lining elongated tubular articles with a non-metallic tubular liner bonded to the interior surface of the tubular article.
2. Brief Description of the Prior Art
It is well known to line metallic tubulars with a non-metallic liner, such as a plastic liner, bonded to the interior of the metallic tubular. This protects the metallic tubular from corrosion resulting from corrosive media passing through the tubular.
With conventional lined tubular products of this type, and methods and apparatus used for production thereof, there are significant problems. Specifically, there is a potential for voids and porosity to exist in the medium used to fill the annular space between the liner and the metal tubular. In addition, the lack of bonding between the annular filler medium and the liner and the metal tube lead to the likelihood of liner movement when the tube is placed in tension or in the presence of pressure buildup due to gas permeation at the interface of either the liner and the filler medium or the filler medium and the internal tubing surface. In addition, the filler medium used in conventional systems offers limited chemical resistance to the environmental conditions encountered in conventional corrosive applications. In this regard, conventional filler mediums offer limited barrier properties with respect to gas and liquid permeation and migration between the liner and the metal tubular.
With respect to the production practices for these lined tubulars, the techniques conventionally employed generally result in poor quality and poor product consistency, which ultimately result in reduced product performance.
Upon application of the non-metallic liner within the tubular, the end flanges conventionally used to protect the tubing ends and provide for sealing of the interfaces of the metal tubular, filler medium, and non-metallic liner are susceptible to damage and possible removal by items passing through the lined tubular. Likewise, the end flanges are susceptible to mechanical damage caused by impact during transport and installation thereof.